:root {
  --color-bg: #f9fafb;
  --color-surface: #ffffff;
  --color-primary: #2563eb;
  --color-primary-dark: #1d4ed8;
  --color-text: #111827;
  --color-text-muted: #4b5563;
  --color-border: #e5e7eb;
  --shadow-soft: 0 10px 25px rgba(15, 23, 42, 0.08);
  --radius-lg: 12px;
  --radius-md: 8px;
  --radius-pill: 999px;
  --transition-fast: 150ms ease-out;
  --max-width: 960px;
}

html {
  scroll-behavior: smooth;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--color-text);
  background: radial-gradient(circle at top left, #e0ebff 0, transparent 55%),
              radial-gradient(circle at bottom right, #e5f6ff 0, transparent 55%),
              var(--color-bg);
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--color-primary);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.25rem;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  backdrop-filter: blur(12px);
  background: linear-gradient(to bottom, rgba(249, 250, 251, 0.96), rgba(249, 250, 251, 0.86));
  border-bottom: 1px solid rgba(209, 213, 219, 0.7);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.85rem 1.25rem;
}

.logo {
  font-weight: 700;
  letter-spacing: 0.03em;
  color: var(--color-text);
}

.main-nav a {
  font-size: 0.95rem;
  color: var(--color-text-muted);
}

.site-main {
  padding: 2rem 0 3rem;
}

.hero {
  padding: 1rem 0 2rem;
}

.hero h1 {
  font-size: clamp(1.8rem, 2.6vw, 2.4rem);
  margin-bottom: 0.5rem;
}

.hero .lead {
  font-size: 1rem;
  color: var(--color-text-muted);
  max-width: 40rem;
}

.tool-list-section h2 {
  font-size: 1.4rem;
  margin-bottom: 0.5rem;
}

.tool-list-section p {
  color: var(--color-text-muted);
}

.tool-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1.2rem;
  margin-top: 1.5rem;
}

.tool-card {
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  padding: 1.1rem 1.1rem 1.05rem;
  box-shadow: var(--shadow-soft);
  border: 1px solid rgba(229, 231, 235, 0.9);
  transition: transform var(--transition-fast), box-shadow var(--transition-fast), border-color var(--transition-fast);
}

.tool-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 18px 40px rgba(15, 23, 42, 0.12);
  border-color: rgba(129, 140, 248, 0.9);
}

.tool-card h3 {
  margin: 0 0 0.4rem;
  font-size: 1.05rem;
}

.tool-card p {
  margin: 0;
  font-size: 0.94rem;
}

.site-footer {
  border-top: 1px solid rgba(209, 213, 219, 0.7);
  background: rgba(249, 250, 251, 0.98);
  padding: 1.2rem 0 1.6rem;
  font-size: 0.85rem;
  color: var(--color-text-muted);
}

.site-footer .container {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
}

.site-footer p {
  margin: 0;
}

.footer-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.footer-nav a {
  font-size: 0.85rem;
  color: var(--color-text-muted);
}

.footer-nav a:hover {
  color: var(--color-primary);
}

.tool-page-main {
  padding: 2rem 0 3rem;
}

.tool-layout {
  display: grid;
  grid-template-columns: minmax(0, 3fr) minmax(0, 2fr);
  gap: 2rem;
}

@media (max-width: 800px) {
  .tool-layout {
    grid-template-columns: 1fr;
  }
}

.card {
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  padding: 1.5rem 1.6rem;
  box-shadow: var(--shadow-soft);
  border: 1px solid rgba(229, 231, 235, 0.95);
}

.tool-header h1 {
  font-size: clamp(1.6rem, 2.4vw, 2rem);
  margin-top: 0;
  margin-bottom: 0.4rem;
}

.tool-header p {
  margin: 0;
  color: var(--color-text-muted);
  font-size: 0.96rem;
}

.tool-form {
  margin-top: 1.25rem;
  display: grid;
  gap: 0.95rem;
}

.form-row {
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
}

.form-row label {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--color-text);
}

.form-row input[type="number"],
.form-row input[type="text"] {
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  padding: 0.55rem 0.65rem;
  font-size: 0.95rem;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast), background-color var(--transition-fast);
}

.form-row input:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 1px rgba(37, 99, 235, 0.35);
  background-color: #f9fbff;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin-top: 0.25rem;
  padding: 0.65rem 1.3rem;
  border-radius: var(--radius-pill);
  border: none;
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-dark));
  color: #ffffff;
  font-weight: 600;
  font-size: 0.97rem;
  cursor: pointer;
  box-shadow: 0 12px 25px rgba(37, 99, 235, 0.35);
  transition: transform var(--transition-fast), box-shadow var(--transition-fast), filter var(--transition-fast);
}

.btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 16px 35px rgba(37, 99, 235, 0.4);
  filter: brightness(1.02);
}

.btn-primary:active {
  transform: translateY(0);
  box-shadow: 0 10px 20px rgba(37, 99, 235, 0.3);
}

.result-box {
  margin-top: 1.1rem;
  padding: 0.85rem 1rem;
  border-radius: var(--radius-md);
  background: #eff6ff;
  border: 1px solid #bfdbfe;
  color: #1e3a8a;
  font-size: 0.96rem;
}

.result-box strong {
  font-weight: 600;
}

.result-heading {
  text-transform: uppercase;
  font-size: 0.8rem;
  letter-spacing: 0.08em;
  opacity: 0.9;
}

.result-main-value {
  margin-top: 0.25rem;
  font-size: 1.4rem;
  font-weight: 700;
}

.result-extra {
  margin-top: 0.5rem;
  font-size: 0.9rem;
}

.helper-text {
  font-size: 0.8rem;
  color: var(--color-text-muted);
}

.ad-banner {
  margin-top: 1.5rem;
  padding: 0.85rem;
  border-radius: var(--radius-md);
  border: 1px dashed #d1d5db;
  text-align: center;
  font-size: 0.85rem;
  color: var(--color-text-muted);
  background: rgba(249, 250, 251, 0.7);
}

.seo-section {
  margin-top: 1.4rem;
}

.seo-section h2 {
  font-size: 1.1rem;
  margin-top: 0;
}

.seo-section p,
.seo-section ul {
  font-size: 0.94rem;
  color: var(--color-text-muted);
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  font-size: 0.75rem;
  padding: 0.18rem 0.7rem;
  border-radius: var(--radius-pill);
  border: 1px solid rgba(191, 219, 254, 0.9);
  background: rgba(239, 246, 255, 0.9);
  color: #1d4ed8;
}

.badge-dot {
  width: 7px;
  height: 7px;
  border-radius: 999px;
  background: #22c55e;
  box-shadow: 0 0 0 4px rgba(34, 197, 94, 0.25);
}

.stacked-heading {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  margin-bottom: 0.8rem;
}

.pill-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin: 0.6rem 0 0;
  padding: 0;
  list-style: none;
}

.pill-list li {
  border-radius: var(--radius-pill);
  background: rgba(17, 24, 39, 0.03);
  padding: 0.15rem 0.6rem;
  font-size: 0.75rem;
  color: var(--color-text-muted);
}

.inline-list {
  padding-left: 1.1rem;
}

.inline-list li {
  margin-bottom: 0.15rem;
}

.tagline {
  font-size: 0.8rem;
  color: var(--color-text-muted);
}

@media (max-width: 600px) {
  .site-header .container {
    padding-inline: 1rem;
  }

  .card {
    padding: 1.2rem 1.25rem;
  }
}